JP5159577B2 - Permanent magnet rotating electric machine - Google Patents

Description

  The present invention uses two or more types of permanent magnets, and irreversibly changes the amount of magnetic flux of at least one of the permanent magnets, thereby enabling a variable speed operation in a wide range from low speed to high speed. It relates to a rotating electrical machine.

  Generally, permanent magnet type rotating electrical machines are roughly divided into two types. They are a surface magnet type permanent magnet type rotating electrical machine in which a permanent magnet is attached to the outer periphery of a rotor core, and an embedded type permanent magnet type rotating electrical machine in which a permanent magnet is embedded in a rotor core. As the variable speed drive motor, an embedded permanent magnet type rotating electrical machine is suitable.

  In the permanent magnet type rotating electrical machine, the interlinkage magnetic flux of the permanent magnet is always generated with a constant strength, so that the induced voltage by the permanent magnet increases in proportion to the rotational speed. Therefore, when variable speed operation is performed from low speed to high speed, the induced voltage (back electromotive voltage) by the permanent magnet becomes extremely high at high speed rotation. When the induced voltage by the permanent magnet is applied to the electronic component of the inverter and exceeds its withstand voltage, the electronic component breaks down. For this reason, it is conceivable to perform a design in which the amount of magnetic flux of the permanent magnet is reduced so as to be equal to or less than the withstand voltage.

  When performing variable speed operation close to constant output from low speed to high speed, the interlinkage magnetic flux on the right of the permanent magnet is constant, so the rotating electrical machine voltage reaches the upper limit of the power supply voltage in the high-speed rotation range, and the current required for output flows. Disappear. As a result, the output is greatly reduced in the high-speed rotation region, and further, variable speed operation cannot be performed over a wide range up to high-speed rotation.

  Recently, as a method for expanding the variable speed range, the flux-weakening control as described in Non-Patent Document 1 has begun to be applied. The total amount of interlinkage magnetic flux of the armature winding is composed of a magnetic flux caused by a d-axis current and a magnetic flux caused by a permanent magnet. In the flux weakening control, by generating a magnetic flux due to a negative d-axis current, the total flux linkage is reduced by the magnetic flux due to this negative d-axis current. Even in the flux-weakening control, the permanent magnet having a high coercive force changes the operating point of the magnetic characteristics (BH characteristics) within a reversible range. For this reason, the NdFeB magnet having a high coercive force is applied to the permanent magnet so that the permanent magnet is not irreversibly demagnetized by the demagnetizing field of the magnetic flux control.

  In operation using the flux-weakening control, the linkage flux decreases due to the magnetic flux due to the negative d-axis current, and therefore the decrease in linkage flux creates a voltage margin with respect to the voltage upper limit value. And since the electric current which becomes a torque component can be increased, the output in a high speed region increases. Further, the rotational speed can be increased by the voltage margin, and the range of variable speed operation is expanded.

  However, since the negative d-axis current that does not contribute to the output is constantly flowing, the copper loss increases and the efficiency deteriorates. Further, the demagnetizing field due to the negative d-axis current generates a harmonic magnetic flux, and the increase in the voltage generated by the harmonic magnetic flux or the like is weakened to create a limit of voltage reduction by the magnetic flux control. Therefore, even if the flux-weakening control is applied to the embedded permanent magnet type rotating electrical machine, it is difficult to perform variable speed operation at three times the specified speed or more. Furthermore, there is a problem that the iron loss increases due to the above-described harmonic magnetic flux, and the efficiency is greatly lowered in the middle and high speed ranges. Further, there is a possibility that vibration is generated by electromagnetic force generated by the harmonic magnetic flux.

  When an embedded permanent magnet motor is applied to a drive motor for a hybrid vehicle, the motor is rotated when driven by an engine alone. In medium / high speed rotation, the induced voltage of the motor's permanent magnet rises. Therefore, in order to suppress it within the power supply voltage, the negative d-axis current is kept flowing by the flux weakening control. In this state, since the electric motor generates only a loss, the overall operation efficiency is deteriorated.

  When an embedded permanent magnet motor is applied to a train drive motor, the train is in a coasting state, and in the same way as above, a negative d-axis current is controlled by a weak magnetic flux control so that the induced voltage by the permanent magnet is lower than the power supply voltage. Keep flowing. In that case, since the electric motor generates only a loss, the overall operation efficiency deteriorates.

  As a technique for solving such a problem, Patent Documents 1 and 2 disclose a permanent magnet having a low coercive force (hereinafter, referred to as “magnetic coercive force”) whose magnetic flux density is irreversibly changed by a magnetic field generated by a current of a stator winding. Variable magnets) and high coercivity permanent magnets (hereinafter referred to as fixed magnets) that have a coercive force more than twice that of variable magnets. A technique is described in which the amount of total interlinkage magnetic flux is adjusted by magnetizing a variable magnetic magnet with a magnetic field generated by a current so that the total interlinkage magnetic flux between the magnet and the fixed magnetic magnet is reduced.

  The permanent magnet type rotating electrical machine of Patent Document 1 includes a rotor 1 having a configuration as shown in FIG. That is, the rotor 1 includes a rotor core 2, eight variable magnetic magnets 3, and eight fixed magnetic magnets 4. The rotor core 2 is configured by laminating silicon steel plates, the variable magnetic force magnet 3 is an alnico magnet or an FeCrCo magnet, and the fixed magnetic force magnet 4 is an NdFeB magnet.

  The variable magnetic force magnet 3 is embedded in the rotor core 2, and first cavities 5 are provided at both ends of the variable magnetic force magnet 3. The variable magnetic force magnet 3 is disposed along the radial direction of the rotor that coincides with the q axis serving as the central axis between the magnetic poles, and is magnetized in a direction perpendicular to the radial direction. The fixed magnetic magnet 4 is embedded in the rotor core 2, and second cavities 6 are provided at both ends of the fixed magnetic magnet 4. The fixed magnetic magnet 4 is disposed substantially in the circumferential direction of the rotor 1 so as to be sandwiched between the two variable magnetic magnets 3 on the inner peripheral side of the rotor 1. The fixed magnetic magnet 4 is magnetized in a direction substantially perpendicular to the circumferential direction of the rotor 1.

  The magnetic pole portion 7 of the rotor core 2 is formed so as to be surrounded by two variable magnetic magnets 3 and one fixed magnetic magnet 4. The central axis direction of the magnetic pole part 7 of the rotor core 2 is the d axis, and the central axis direction between the magnetic poles is the q axis. In the permanent magnet type rotating electrical machine of Patent Document 1 adopting this rotor 1, a magnetic field is formed by passing a pulsed current whose energization time is extremely short (about 100 μs to 1 ms) to the stator winding to make it variable. A magnetic field is applied to the magnetic magnet 3. If the magnetizing magnetic field is 250 kA / m, ideally, a sufficient magnetizing magnetic field acts on the variable magnetic force magnet 3, and the fixed magnetic force magnet 4 does not undergo irreversible demagnetization due to magnetization.

  As a result, in the permanent magnet type rotating electrical machine disclosed in Patent Document 1, the amount of interlinkage magnetic flux of the variable magnetic force magnet 3 can be greatly changed from the maximum to 0 by the d-axis current of the rotor 1, and the magnetization direction can be changed in both forward and reverse directions. . That is, assuming that the linkage magnetic flux of the fixed magnetic magnet 4 is in the positive direction, the linkage magnetic flux of the variable magnetic magnet 3 can be adjusted over a wide range from the maximum value in the positive direction to 0 and further in the reverse direction. Therefore, in the rotor of the present embodiment, the total interlinkage magnetic flux combined with the variable magnetic magnet 3 and the fixed magnetic magnet 4 can be adjusted over a wide range by magnetizing the variable magnetic magnet 3 with the d-axis current. .

For example, in the low speed range, the variable magnetic magnet 3 is magnetized with the d-axis current so as to have the maximum value in the same direction (initial state) as the interlinkage magnetic flux of the fixed magnetic magnet 4, so that the torque by the permanent magnet becomes the maximum value. Therefore, the torque and output of the rotating electrical machine can be maximized. In the middle / high speed range, the voltage of the rotating electrical machine is lowered by reducing the amount of magnetic flux of the variable magnetic magnet 3 and lowering the total flux linkage, so that there is room for the upper limit of the power supply voltage and the rotational speed ( (Frequency) can be further increased.
JP 2006-280195 A JP 2008-48514 A

  In the permanent magnet type rotating electrical machine of Patent Document 1 having the above-described configuration, the amount of interlinkage magnetic flux of the variable magnetic force magnet 3 can be greatly changed from the maximum to 0 by the d-axis current of the rotor 1, and the magnetization direction is also positive. It has an excellent characteristic that it can be made in both opposite directions. On the other hand, when magnetizing the variable magnetic force magnet 3, a large magnetizing current is required, which leads to an increase in the size of an inverter for driving the electric motor.

  In particular, due to the characteristics of the permanent magnet, a large magnetizing current is required when the magnet is increased than when the magnet is demagnetized. However, in the permanent magnet type rotating electrical machine disclosed in Patent Document 1, two types of magnets are magnetically arranged in parallel. Due to the configuration, a large magnetic field is required for magnetizing the variable magnetic magnet 3 due to the influence of the interlinkage magnetic flux of the fixed magnetic magnet 4.

  FIGS. 16A to 16D are schematic views for explaining this. In the permanent magnet type rotating electric machine of Patent Document 1, as shown in FIG. 16A, two variable magnetic magnets 3 and one fixed magnetic magnet 4 are arranged in a U shape with the d axis as the center. In the normal operation state of the electric motor, the direction of the magnetic flux of the variable magnetic magnet 3 and the fixed magnetic magnet 4 is directed toward the central magnetic pole portion 7. In this state, when a d-axis current is applied in a pulsed manner to generate a magnetic field for demagnetization, the magnetic flux is changed from the outer peripheral side of the rotor 1 to the variable magnetic magnet 3 and the fixed magnetic magnet as shown in FIG. 4 so that the variable magnetic force magnet 3 is demagnetized. At this time, the fixed magnet 4 is not demagnetized because of its high coercivity.

  In the case of this demagnetization, as shown in FIG. 16C, the magnetic flux of the fixed magnetic magnet 4 is changed from the inner direction of the variable magnetic magnet 3 to the outer side along with the d-axis direction. Flows in the opposite direction, and assists the demagnetizing action by the magnetic field generated by the d-axis current. Therefore, demagnetization until the polarity of the variable magnetic force magnet 3 is reversed is possible.

  On the other hand, in the case of magnetization, a variable magnetic force magnet demagnetized by a reverse magnetic flux that generates a magnetic field in the opposite direction by applying a d-axis current again in a pulsed manner. The flux linkage 3 is returned to the normal operation state of (A). However, originally, a larger energy is required for magnetizing than demagnetization, and the magnetic flux of the fixed magnetic magnet 4 is applied to the variable magnetic magnet 3 in the demagnetizing direction as shown in FIG. Therefore, a magnetizing current that can generate a magnetic field large enough to overcome this is required.

  Thus, since the permanent magnet type rotating electrical machine of Patent Document 1 has two kinds of magnets arranged in parallel magnetically, the amount of demagnetization of the variable magnetic force magnet 3 can be increased, and the change width of the magnetic force can be set to 0 to 0. Although there is an advantage that it can be increased to 100%, there is a problem that a large magnetizing current is required at the time of magnetization.

  Such a problem occurs not only when the magnetism is increased but also when the variable magnetic force magnet 3 is demagnetized, and the appearance of a permanent magnet type rotating electrical machine that can efficiently generate the magnetic flux amount of the variable magnetic force magnet 3 has appeared. It was desired.

  The present invention has been made to solve the above-described problems, and by reducing the magnetizing current at the time of magnetizing the variable magnetic force magnet, it is possible to increase the speed of the inverter from low speed to high speed without requiring an increase in the size of the inverter. It is an object of the present invention to provide a permanent magnet type rotating electrical machine that can be operated at a variable speed in a wide range, can increase torque in a low-speed rotation region, increase output in a medium / high-speed rotation region, and improve efficiency.

  In the present invention, a magnetic pole of a rotor is formed using two or more types of permanent magnets having a product of a coercive force and a magnetization direction thickness different from those of other permanent magnets, and the two or more types of permanent magnets are connected in series on a magnetic circuit. For two or more types of permanent magnets arranged in series, among the two or more types of permanent magnets, permanent magnets having a large product of coercive force and magnetization direction thickness are arranged in parallel on the magnetic circuit. The magnetic field generated by the current of the armature winding magnetizes the permanent magnet having a small product of the coercive force and the magnetization direction thickness among the two or more types of permanent magnets arranged in series to form a magnetic pole. The magnetic flux amount of the permanent magnet is irreversibly changed.

  In the present invention, two or more kinds of permanent magnets are arranged in series and parallel on the magnetic circuit for each magnetic pole of the rotor, and two or more kinds of permanent magnets are arranged in series and parallel on the magnetic circuit between the plurality of magnetic poles. It is also possible to do. Further, it is possible to provide a magnetic barrier or a short-circuit coil for each magnetic pole.

  According to the present invention having the above-described configuration, an increase in the magnetizing current at the time of demagnetization and magnetization of a permanent magnet having a small product of the coercive force and the magnetization direction thickness can be suppressed. Can be achieved.

  Hereinafter, an embodiment of a permanent magnet type rotating electrical machine according to the present invention will be described with reference to FIGS. The rotating electrical machine of the present embodiment has been described in the case of 12 poles, and can be similarly applied to other pole numbers.

(1. First embodiment)
(1-1. Configuration)
A first embodiment of the present invention will be described with reference to FIG.

  The rotor 1 according to the first embodiment of the present invention includes a rotor core 2, a permanent magnet 3 (hereinafter referred to as a variable magnetic force magnet) in which the product of the coercive force and the magnetization direction thickness is small, as shown in FIG. It is composed of permanent magnets (hereinafter referred to as fixed magnetic magnets) 4a and 4b in which the product of the coercive force and the magnetization direction thickness is large. The rotor core 2 is formed by laminating silicon steel plates, and the variable magnetic magnet 3 and the fixed magnetic magnets 4 a and 4 b are embedded in the rotor core 2.

  A cavity is formed at the ends of the variable magnetic magnet 3 and the fixed magnetic magnets 4a and 4b so that the magnetic flux passing through the rotor core 2 passes through the portions of the variable magnetic magnet 3 and the fixed magnetic magnets 4a and 4b in the thickness direction. 6 is provided. The magnetic pole portion 7 of the rotor core 2 is formed so as to be surrounded by one variable magnetic force magnet 3 and three fixed magnetic force magnets 4a and 4b. The central axis direction of the magnetic pole part 7 of the rotor core 2 is the d axis, and the central axis direction between the magnetic poles is the q axis.

  The variable magnetic magnet 3 can be a ferrite magnet or an alnico magnet. The fixed magnetic magnets 4a and 4b are NdFeB magnets. In the present embodiment, the coercive force of the ferrite magnet is 280 kA / m, and the coercive force of the NdFeB magnet is 1000 kA / m.

  The variable magnetic magnet 3 and the fixed magnetic magnet 4a are superposed in the magnetization direction of each magnet to constitute one magnet. That is, the variable magnetic magnet 3 and the fixed magnetic magnet 4a are magnetically arranged in series with the same magnetization direction. The magnets stacked in series are arranged in the rotor core 2 at a position where the magnetization direction is the d-axis direction (here, approximately the radial direction of the rotor). On the other hand, the fixed magnetic magnets 4b and 4b are arranged on both sides of a magnet in which the variable magnetic magnet 3 and the fixed magnetic magnet 4a are stacked in series at a position where the magnetization direction is the d-axis direction. The fixed magnetic magnets 4b and 4b arranged beside the above constitute a parallel circuit on the magnetic circuit with respect to the magnets stacked in series. That is, on the magnetic circuit, the fixed magnetic magnet 4a is arranged in series with the variable magnetic magnet 3, and the fixed magnetic magnets 4b and 4b are arranged in parallel.

  Short circuit coils 8 are provided on the upper side and the lower side so as to surround the magnet in which the variable magnetic magnet 3 and the fixed magnetic magnet 4a are laminated and the fixed magnetic magnets 4b and 4b on both sides, embedded in the rotor core 2. . At this time, the short-circuit coil 8 is set so that the magnetization direction of the fixed magnetic magnets 4b and 4b is the central axis. The short-circuit coil 8 is composed of a ring-shaped conductive member, and is mounted so as to fit into the edge portion of the cavity 6 provided in the rotor core 2. It is also possible to manufacture by casting a conductive member melted at a high temperature into the hole of the rotor core 2. The short-circuit coil 8 is provided in the magnetic path portion of the other fixed magnetic magnets 4b and 4b excluding the variable magnetic magnet 3.

  The short-circuit coil 8 is a magnetic flux generated when a d-axis current is passed through the armature winding and generates a short-circuit current. The short-circuit current flowing in the short-circuit coil 8 preferably flows within 1 second with such a strength that the magnetization of the permanent magnet 3 to be irreversibly changed, and then attenuates 50% or more within 1 second. Further, when the inductance value and the resistance value of the short-circuit coil 8 are set to values that allow a short-circuit current to flow to the extent that the magnetization of the variable magnetic force magnet 3 changes, the efficiency is good.

  A stator 10 is provided on the outer periphery of the rotor 2 through an air gap. The stator 10 has an armature core 11 and an armature winding 12. An induced current is induced in the short-circuit coil 8 by the magnetizing current flowing through the armature winding 12, and a magnetic flux penetrating the short-circuit coil 8 is formed by the induced current. Further, the magnetization direction of the variable magnetic force magnet 3 is irreversibly changed by the magnetization current flowing through the armature winding 12.

  That is, for the variable magnetic magnet 3 and the fixed magnetic magnet 4a, during operation of the permanent magnet type rotating electric machine, the variable magnetic magnet 3 is magnetized by a magnetic field generated by the d-axis current, and the amount of the magnetic flux is irreversibly changed. . In this case, the d-axis current for magnetizing the variable magnetic force magnet 3 is supplied, and at the same time the torque of the rotating electrical machine is controlled by the q-axis current.

  Also, the amount of interlinkage magnetic flux in the armature winding generated by the current (the total current obtained by combining the q-axis current and the d-axis current) and the variable magnetic magnet 3 and the fixed magnetic magnets 4a and 4b by the magnetic flux generated by the d-axis current. That is, the amount of interlinkage magnetic flux of the entire armature winding composed of the magnetic flux generated in the armature winding by the total current of the rotating electrical machine and the magnetic flux generated by the two or more kinds of permanent magnets 4a and 4b on the rotor side. Change almost reversibly.

  In particular, in the present embodiment, the variable magnetic force magnet 3 is irreversibly changed by a magnetic field generated by a large instantaneous d-axis current. In this state, operation is carried out by continuously supplying a d-axis current in a range where little or no irreversible demagnetization occurs. The d-axis current at this time acts to adjust the terminal voltage by advancing the current phase.

  Further, an operation control method is performed in which the polarity of the variable magnetic force magnet 3 is reversed with a large d-axis current to advance the current phase. As described above, since the polarity of the variable magnetic force magnet 3 is reversed by the d-axis current, even if a negative d-axis current that reduces the terminal voltage is passed, the variable magnetic force magnet 3 is not demagnetized but increased. Become. That is, the magnitude of the terminal voltage can be adjusted without demagnetizing the variable magnetic force magnet 3 with a negative d-axis current.

  In a general magnet motor, since the polarity of the magnet is not reversed, if the d-axis current increases by advancing the current phase, there is a problem that the magnet is irreversibly demagnetized. It is possible to advance the phase by reversing the polarity.

(1-2. Basic action)
Next, the operation of the first embodiment will be described.
In the present embodiment, a magnetic field is formed by applying a pulsed current having a very short energization time (about 0.1 ms to 100 ms) to the armature winding of the stator, and the magnetic field is applied to the variable magnetic force magnet 3. Let A pulse current that forms a magnetic field for magnetizing the variable magnetic force magnet 3 is a d-axis current component of the armature winding of the stator.

If the thicknesses of the two types of permanent magnets 4a and 4b are substantially equal, the change in the magnetization state of the permanent magnet due to the applied magnetic field due to the d-axis current varies depending on the magnitude of the coercive force. That is, the change in the magnetization state of the permanent magnet due to the applied magnetic field is approximated by the product of the magnitude of the coercive force and the thickness of the permanent magnet. In this embodiment, the coercive force of the ferrite magnet is 300 kA / m, and the coercive force of the NdFeB magnet is 1000 kA / m. The magnet thickness in the magnetization direction is the same, 5 mm. The magnetomotive force required for magnetization is estimated by the product of the magnetic field required for magnetization and the thickness of the permanent magnet. The 90% magnetization magnetic field of the ferrite magnet is about 350 kA / m, so the magnetomotive force required for magnetization is 350 kA / m × 5 ×. 10 ⁻³ = 1750A. On the other hand, since the 90% magnetization magnetic field of the NdFeB magnet is about 1500 kA / m, the magnetomotive force required for magnetization is 1500 kA / m × 5 × 10 ⁻³ = 7500 A.

  The magnetomotive force required to change the magnetic force of the ferrite magnet that is the variable magnetic magnet 3 is about 20% of the NdFeB magnet that is the fixed magnetic magnets 4a and 4b. Therefore, the magnetic force of the NdFeB magnet can be maintained unchanged with a current that can change the magnetic force of the ferrite magnet. Thus, when these magnets are combined in series to form a magnet, the total flux linkage of the permanent magnet can be adjusted by maintaining the magnetic force of the NdFeB magnet as a base and changing the magnetic force of the ferrite magnet.

  First, a negative d-axis current that generates a magnetic field in a direction opposite to the magnetization direction of the magnet is applied to the armature winding in a pulsed manner. If the magnetic field in the magnet changed by the negative d-axis current is 175 kA / m, the magnetic force of the ferrite magnet is irreversibly greatly reduced because the coercive force of the ferrite magnet is 175 kA / m. On the other hand, since the coercive force of the NdFeB magnet is 1500 kA / m, the magnetic force does not decrease irreversibly. As a result, when the pulsed d-axis current becomes 0, only the ferrite magnet is demagnetized, and the amount of flux linkage by the entire magnet can be reduced.

  Next, a positive d-axis current that generates a magnetic field in the same direction as the magnetization direction of the permanent magnet is applied to the armature winding. A magnetic field necessary for magnetizing the ferrite magnet is generated. When the magnetic field in the magnet changed by the positive d-axis current is 350 kA / m, the demagnetized ferrite magnet is magnetized to generate a maximum magnetic force. On the other hand, since the coercive force of the NdFeB magnet is 1500 kA / m, the magnetic force does not change irreversibly. As a result, when the pulsed positive d-axis current becomes zero, only the ferrite magnet is magnetized, and the amount of flux linkage by the entire magnet can be increased. This makes it possible to return to the original maximum flux linkage.

  As described above, by applying an instantaneous magnetic field due to the d-axis current to the ferrite magnet and the NdFeB magnet, the magnetic force of the ferrite magnet is irreversibly changed, and the total interlinkage magnetic flux amount of the permanent magnet is arbitrarily changed. Is possible.

  In this case, the variable magnetic force magnet 3 is magnetized so that the magnetic flux of the permanent magnet of the magnetic pole is added at the time of the maximum torque of the permanent magnet type rotating electric machine. The variable magnetic force magnet 3 is magnetized by a magnetic field generated by an electric current to reduce the magnetic flux. In addition, when the rotor reaches the maximum rotational speed with the magnetic flux magnet minimized by irreversibly changing the magnetic pole magnet, the induced electromotive force generated by the permanent magnet is resistant to the inverter electronic components that are the power source of the rotating electrical machine. Below voltage.

(1-3. Action of serial arrangement)
In the present embodiment, since two types of magnets are magnetically arranged in series, when the variable magnetic force magnet 3 is demagnetized and magnetized, the action is different from that of the permanent magnet type rotating electrical machine of Patent Document 1. Have This point will be described with reference to FIGS.

  FIG. 2 is a diagram in a case where the maximum amount of flux linkage before demagnetization is obtained. In this case, since the magnetization directions of the two types of permanent magnets 3 and 4a are the same, the magnetic fluxes of both permanent magnets 3 and 4a are added together to obtain the maximum amount of magnetic flux.

  FIG. 3 shows a state at the time of demagnetization, and the armature generates a negative d-axis current that generates a magnetic field in a direction opposite to the magnetization direction of both permanent magnets 3 and 4a from the d-axis direction by the armature winding. Energize the winding in pulses. If the magnetic field in the magnet changed by the negative d-axis current becomes 175 kA / m, the coercive force of the variable magnetic magnet 3 (ferrite magnet) is 175 kA / m, so the magnetic force of the variable magnetic magnet 3 is irreversibly significantly reduced. To do. In this case, the magnetic field from the fixed magnetic field magnet 4a laminated on the variable magnetic field magnet 3 is applied to the variable magnetic field magnet 3 and this cancels out the magnetic field applied from the d-axis direction for demagnetization. However, since the magnetization current for demagnetization is smaller than that at the time of magnetization, the increase in the magnetization current is small.

  FIG. 4 shows a state in which the magnetic force of the variable magnetic force magnet 3 in a reverse magnetic field is reduced by a negative d-axis current. Although the magnetic force of the variable magnetic force magnet 3 is irreversibly significantly reduced, the magnetic force is not irreversibly lowered because the coercive force of the fixed magnetic force magnet 4a (NdFeB magnet) is 1500 kA / m. As a result, when the pulsed d-axis current becomes zero, only the variable magnetic force magnet 3 is demagnetized, and the amount of interlinkage magnetic flux by the entire magnet can be reduced.

  FIG. 5 shows a state in which the magnetic force of the variable magnetic force magnet 3 in the reverse magnetic field is magnetized in the reverse direction by the negative d-axis current, and the linkage flux by the entire magnet is minimized. If the magnitude of the negative d-axis current generates a magnetic field of 350 kA / m necessary for magnetizing the variable magnetic force magnet 3, the demagnetized variable magnetic force magnet 3 is magnetized to generate a magnetic force. Occur. In this case, since the magnetization directions of the two types of permanent magnets 3 and 4a are opposite to each other, the magnetic fluxes of both permanent magnets are subtracted to minimize the magnetic flux.

  FIG. 6 shows a state where a magnetic field is generated in order to reduce the magnetic force of the variable magnetic magnet 3 whose polarity is reversed by a negative d-axis current. A positive d-axis current that generates a magnetic field in the magnetization direction of the fixed magnetic force magnet 4a is pulsed through the armature winding. The magnetic field in the magnet changed by the positive d-axis current irreversibly greatly reduces the magnetic force of the variable magnetic magnet 3 whose polarity is reversed. In this case, the magnetic field from the fixed magnetic magnet 4a stacked on the variable magnetic magnet 3 is added to the magnetic field generated by the magnetizing current (a biased magnetic field acts on the variable magnetic magnet 3 from the fixed magnetic magnet 4a). Demagnetization of the variable magnetic force magnet 3 is easily performed.

  FIG. 7 shows a state where the magnetic force of the variable magnetic force magnet 3 whose polarity is reversed by a magnetic field due to a positive d-axis current is reduced. The magnetic field generated by the fixed magnetic force magnet 4a is also added to the magnetic field generated by the positive d-axis current that irreversibly decreases the magnetic force of the variable magnetic force magnet 3. Therefore, even when a large magnetizing current is usually required, an increase in the magnetizing current can be suppressed by the action of the fixed magnetic magnet 4a.

  FIG. 8 shows a state in which the variable magnetic force magnet 3 is magnetized in the reverse direction (polarity is reversed again) by the positive d-axis current, and the interlinkage magnetic flux by the entire magnet is maximized. Since the magnetization directions of the two types of permanent magnets 3 and 4a are the same, the magnetic fluxes of both permanent magnets are added together to obtain the maximum amount of magnetic flux.

(1-4. Action of variable magnetic magnet)
Next, the operation of the variable magnetic force magnet 3 will be described. FIG. 9 is a graph showing the magnetic characteristics (relationship between coercive force and magnetic flux density) of typical magnets such as an NdFeB magnet, a ferrite magnet, an alnico magnet, and a sumakoba magnet. Among them, an NdFeB magnet can be used as the fixed magnetic magnet 4 of the present invention, and a ferrite magnet, an alnico magnet, or a samacoba magnet (samarium cobalt magnet) can be used as the variable magnetic magnet 3. In the present embodiment, a ferrite magnet 3 is used as the variable magnetic force magnet 3.

  Even if the variable magnetic force magnet 3 has a low coercive force, the variable magnetic force magnet 3 has a high magnetic flux density when only the variable magnetic force magnet 3 is in a state. The operating point decreases, and the magnetic flux density decreases. On the other hand, in the state where the variable magnetic magnet 3 and the fixed magnetic magnet 4a are stacked in series, the action of the fixed magnetic magnet 4a stacked in series raises the operating point of the magnet of the variable magnetic magnet 3 and the magnetic flux density is increased. To rise.

  That is, the operating point of the Alnico magnet or the Samacoba magnet, which is a magnet having a low coercive force and a high magnetic flux density, is on the high magnetic flux density side (A and B in FIG. 9) when only the variable magnetic magnet 3 is used. In the state where 4b and 4b are arranged in parallel, the magnetic flux density decreases to the low magnetic flux density side (A ′ and B ′ in FIG. 9). However, in the state where the variable magnetic magnet 3 and the fixed magnetic magnet 4a are stacked in series as in the present embodiment, the fixed magnetic magnets 4b and 4b arranged in parallel and the fixed magnetic magnet 4a arranged in series. Since the directions of the magnetic fields are opposite, the magnetic fields of both are canceled out, and the operating point of the variable magnetic force magnet 3 moves to the high magnetic flux density side (A ″, B ″ in FIG. 9).

  As can be seen from this graph, when an Alnico magnet or a Samacoba magnet is used alone as the variable magnetic force magnet 3, in order to lower the magnetic flux density from the operating points A and B, the magnetic force that can overcome the coercive force is sufficient. Must be generated by a magnetic field generated by the d-axis current of the armature winding, and a large d-axis current is required. However, as in the present embodiment, the operating point of the variable magnetic force magnet 3 moves to A ″ in the figure by the fixed magnetic force magnets 4b and 4b arranged in parallel and the fixed magnetic force magnet 4a arranged in series. As a result, the magnetic flux density is drastically reduced by slightly changing the strength of the magnetic field, whereby the magnetic force of the variable magnetic magnet 3 is reduced by a reverse magnetic field due to the d-axis current of the armature winding. In this case, since the change in the magnetic flux density can be increased, the amount of interlinkage magnetic flux generated by the entire permanent magnet disposed in the magnetic pole can be greatly changed with a small d-axis current.

  Since the ferrite magnet has a larger coercive force than the alnico magnet, the magnetization current required when the polarity is reversed in the direction in which the interlinkage magnetic flux of the permanent magnet is increased. However, in this embodiment, the magnetic force can be reversed with a small magnetization current by the action of the fixed magnetic magnets arranged in series.

  This point is the same when the ferrite magnet shown in FIG. 9 is used as the variable magnetic force magnet 3, and there is no abrupt change as in the case of the Alnico magnet or the Samacoba magnet, but compared with the case where the ferrite magnet is used alone. Since the operating point C ″ is lowered, the magnetic flux density can be lowered with a small d-axis current.

(1-5. Action of magnetic barrier)
The action of the magnetic barrier provided on the outer periphery of the fixed magnetic magnets 4a and 4b will be described with reference to FIG. The cavities 5 and 6 serving as magnetic barriers are provided not on the outer peripheral portion of the magnet in which the variable magnetic force magnet 3 and the fixed magnetic force magnet 4a are stacked, but on the outer peripheral portions of the fixed magnetic force magnets 4b and 4b arranged in parallel. Since the fixed magnetic magnets 4b and 4b have a magnetic barrier, the magnetic field due to the d-axis current is reduced.

  On the other hand, since there is no magnetic barrier around the magnet in which the variable magnetic magnet 3 and the fixed magnetic magnet 4a are laminated, the magnetic field generated by the d-axis current can be increased. Thus, the magnetic field A caused by the d-axis current can be effectively applied to the magnet in which the variable magnetic magnet 3 and the fixed magnetic magnet 4a are laminated. Further, regarding the magnetic flux that increases due to the d-axis current, the increase in the amount of magnetic flux passing through the fixed magnetic magnets 4b and 4b can be suppressed, so that the magnetic saturation of the iron core can be reduced and the d-axis for changing the magnetization of the variable magnetic magnet 3 The current can also be reduced.

  In addition, as shown in FIG. 11, the q-axis magnetic flux B is distributed so as to cross the iron core on the outer periphery of the magnet. However, since there are cavities 5 and 6 serving as magnetic barriers, the magnetic path cross-sectional area is narrowed and the magnetic resistance is high. Become. Therefore, the q-axis inductance can be reduced and the terminal voltage can be lowered.

(1-6. Action of short-circuit coil)
Next, the operation of the short-circuit coil 8 will be described with reference to FIG. Since the variable magnetic magnet 3 and the fixed magnetic magnets 4a and 4b are embedded in the rotor core 2 to form a magnetic circuit, the magnetic field generated by the d-axis current is not limited to the variable magnetic magnet 3 but also the fixed magnetic magnet 4a. , 4b. Originally, the magnetic field generated by the d-axis current is used to change the magnetization of the variable magnetic force magnet 3.

  Therefore, the magnetic field due to the d-axis current may be prevented from acting on the fixed magnetic magnets 4 b and 4 b and concentrated on the variable magnetic magnet 3. In the present embodiment, short-circuit coils 8 are arranged on the upper and lower sides of the fixed magnetic magnets 4b and 4b. The short-circuit coil is arranged with the magnetization direction of the fixed magnetic magnets 4b and 4b as the central axis. When a magnetic field due to the d-axis current acts on the fixed magnetic magnets 4 b and 4 b, an induced current that cancels the magnetic field flows through the short-circuit coil 8. Therefore, in the fixed magnetic force magnets 4b and 4b, there is almost no increase or decrease in the magnetic field due to the magnetic field due to the d-axis current and the magnetic field due to the short-circuit current. Furthermore, the magnetic field due to the short-circuit current also acts on the variable magnetic force magnet 3 and is in the same direction as the magnetic field due to the d-axis current.

  Therefore, the magnetic field that magnetizes the variable magnetic force magnet 3 is strengthened, and the variable magnetic force magnet 3 can be magnetized with a small d-axis current. Further, since the fixed magnetic magnets 4b and 4b are not affected by the d-axis current due to the short-circuit coil, and the magnetic flux hardly increases, the magnetic saturation of the armature core due to the d-axis current can be reduced.

  In addition, instead of the short-circuit coil 8, a conductive plate can be provided on the lower surfaces of the fixed magnetic magnets 4b and 4b (the inner peripheral side of the rotor). It is preferable to use a copper plate or an aluminum plate as the conductive plate. Further, the conductive plate is not limited to the lower surface of the fixed magnetic magnets 4b, 4b, but may be disposed on the upper surface (the outer peripheral side of the rotor). There is a merit that an induced current is generated in the insulating plate and the harmonics can be reduced.

  In such a configuration, when a magnetic field generated by the magnetizing current is applied to the conductive plate, an induced current (eddy current) is generated on the surface of the conductive plate, whereby the same magnetic field as that of the short-circuit coil 8 is generated. Will occur. Due to the magnetic field, in the fixed magnetic magnets 4b and 4b, the magnetic field due to the d-axis current and the magnetic field due to the short-circuit current hardly increase or decrease. Furthermore, the magnetic field due to the short-circuit current also acts on the variable magnetic force magnet 3 and is in the same direction as the magnetic field due to the d-axis current. At the same time, the effect of relaxing the magnetic saturation of the armature core 11 is also exhibited.

(1-7. Action of air gap length)
In the first embodiment, as shown in FIG. 1, the air gap length L1 in the vicinity where the fixed magnetic magnets 4b and 4b are arranged is longer than the air gap length L2 in the vicinity where the variable magnetic magnet 3 is arranged. The configuration is as follows.

  In the present embodiment, the magnetic field due to the d-axis current is intended to act on the variable magnetic magnet 3 and the fixed magnetic magnet 4a, but a leakage magnetic field is also generated. Therefore, in the present embodiment, the air gap length L2 near the q axis is made larger than the air gap length L1 near the d axis. That is, since the air gap length is shorter in the vicinity where the variable magnetic force magnet 3 is disposed, the magnetic resistance of the air gap portion is reduced.

  Accordingly, the magnetic field generated by the d-axis current for magnetizing the magnet can be concentrated on the variable magnetic force magnet 3 disposed in the d-axis portion, and at the same time, a high magnetic field can be applied, and the variable magnetic force can be reduced with a small d-axis current. The magnet 3 can be effectively magnetized. In addition, since the q-axis side magnetic resistance can be increased, the inductance of the rotating electrical machine can be reduced and the power factor can be improved. As another example, a nonmagnetic portion that increases the magnetic resistance in the q-axis direction may be provided in the rotor core.

(1-8. Effect)
In the present embodiment having the configuration and operation as described above, the following effects can be obtained. (1) Since the increase in the magnetizing current at the time of magnetizing can be suppressed, it is not necessary to increase the size of the inverter for driving the permanent magnet type rotating electric machine, and the current inverter can be used as it is to improve the operation efficiency. It becomes.
(2) By irreversibly changing the variable magnetic magnet 3 with the d-axis current, the total interlinkage magnetic flux combined with the fixed magnetic magnet 4a and the fixed magnetic magnets 4b and 4b can be adjusted over a wide range.

(3) The adjustment of the total interlinkage magnetic flux of the permanent magnet makes it possible to adjust the voltage of the rotating electrical machine over a wide range, and the magnetization is always weakened by performing a pulse current in an extremely short time. Since it is not necessary to continue the flow, the loss can be greatly reduced. Further, since it is not necessary to perform the flux-weakening control as in the prior art, harmonic iron loss due to the harmonic magnetic flux does not occur. As described above, the rotating electrical machine according to the present embodiment enables high-output, wide-range variable speed operation from low speed to high speed, and high efficiency in a wide operation range.

(4) Regarding the induced voltage due to the permanent magnet, the variable magnetic force magnet 3 can be magnetized with a negative d-axis current to reduce the total flux linkage of the permanent magnet. And the reliability is improved.

(5) In a state where the rotating electrical machine is rotated with no load, the total magnetic flux linkage of the permanent magnet can be reduced by magnetizing the variable magnetic force magnet 3 with a negative d-axis current. As a result, the induced voltage is remarkably lowered, and there is almost no need to constantly apply a weak magnetic flux current for lowering the induced voltage, thereby improving the overall efficiency. In particular, when the rotating electric machine of the present embodiment is mounted on a commuter train that has a long coasting operation time, the overall driving efficiency is greatly improved.

(2. Second Embodiment)
A second embodiment of the present invention will be described with reference to FIG.
In the present embodiment, as shown in FIG. 13, the fixed magnetic magnets 4b and 4b are arranged on both sides of the variable magnetic magnet 3 to constitute the first magnetic pole of the rotor. On the other hand, a fixed magnetic force magnet 4a is disposed adjacent to the first magnetic pole to constitute a second magnetic pole. The polarities of the fixed magnetic magnets 4a and 4b in the adjacent first and second magnetic poles are arranged to have different polarities on the outer peripheral side and the inner peripheral side of the rotor.

  That is, a first magnetic pole in which fixed magnetic magnets 4b and 4b are arranged on both sides of the variable magnetic magnet 3, and a fixed magnetic magnet 4b and 4b of the first magnetic pole arranged on both sides of the first magnetic pole. The magnetic poles of the rotor are formed from the second magnetic poles configured by using the fixed magnetic force magnets 4a having different values. In the first magnetic pole, the variable magnetic magnet 3 and the fixed magnetic magnets 4b and 4b are arranged in parallel on the magnetic circuit, and the fixed magnetic force arranged on the variable magnetic magnet 3 of the first magnetic pole and the second magnetic pole. Magnets 4a are arranged in series on the magnetic circuit.

  In the present embodiment having the above-described configuration, the variable magnetic force magnet 3 is not arranged in series with the fixed magnetic force magnet in one pole of the rotor. However, since the variable magnetic force magnet 3 is affected by the magnetic field of the fixed magnetic force magnet 4a of the adjacent pole, the same effect as when the fixed magnetic force magnet 4a is laminated as in the above embodiment can be obtained. That is, the magnetic field of the fixed magnetic magnet 4 a at the pole of the adjacent rotor is opposite to the magnetic field of the fixed magnetic magnets 4 b and 4 b arranged in parallel to the variable magnetic magnet 3 inside the variable magnetic magnet 3. , Act to offset each other. Accordingly, when the variable magnetic force magnet 3 is magnetized from the irreversible demagnetized state and returned to the original polarity, the magnetic field by the adjacent fixed magnetic force magnets 4b and 4b that hinder the change can be reduced. The magnetizing current (d-axis current) required when changing the magnetic force 3 can be reduced.

(3. Third embodiment)
A third embodiment of the present invention will be described with reference to FIG.
In the present embodiment, as shown in FIG. 14, the single magnetized magnet 4 b is positioned at the position where the magnetization direction is the d-axis direction (here, substantially the radial direction of the rotor) (the center portion of the stator core). In the rotor core 2. On the other hand, magnets in which the variable magnetic magnet 3 and the fixed magnetic magnet 4a are stacked in series are arranged on both sides of the fixed magnetic magnet 4b at positions where the magnetization direction is the d-axis direction. The magnet in which the variable magnetic magnet 3 and the fixed magnetic magnet 4a arranged on both sides are stacked constitutes a parallel circuit on the magnetic circuit with respect to the fixed magnetic magnet 4b at the center of the magnetic pole.

  The cavity 6 is formed at the end of the variable magnetic magnet 3 and the fixed magnetic magnet 4a so that the magnetic flux passing through the rotor core 2 passes through the portions of the variable magnetic magnet 3 and the fixed magnetic magnet 4a in the thickness direction. Provide.

  In the present embodiment having the above-described configuration, in addition to the same effects as the above-described embodiment, a magnet in which the variable magnetic magnet 3 and the fixed magnetic magnet 4a are stacked on the left and right with respect to the magnetic pole is disposed. Therefore, the variable magnetic force magnet 3 can be magnetized by dividing the left and right sides twice. As a result, there is only one fixed magnetic magnet 4b arranged in parallel that will prevent the polarity change of the variable magnetic magnet 3. That is, compared to the embodiment in which two fixed magnetic magnets 4b are arranged, the magnetic field by the fixed magnetic magnet 4b that prevents the polarity change of the variable magnetic magnet 3 can be reduced, so that the magnetic force of the variable magnetic magnet 3 can be changed. The required magnetizing current (d-axis current) can be reduced.

(4. Other embodiments)
The present invention is not limited to the above-described embodiments, and includes other embodiments as follows.

(1) In each of the above embodiments, a four-pole rotating electric machine is shown, but the present invention is naturally applicable to a multi-pole rotating electric machine such as an eight-pole machine. Depending on the number of poles, the position and shape of the permanent magnets will of course change somewhat, and the action and effect can be obtained in the same way.

(2) In the permanent magnet forming the magnetic pole, the permanent magnet is defined to be distinguished by the product of the coercive force and the thickness in the magnetization direction. Therefore, even if the magnetic poles are formed of the same type of permanent magnet and are formed so as to have different magnetization direction thicknesses, the same operation and effect can be obtained.

(3) In the rotor core 2, in order to determine the shape and position of the cavity provided to form the magnetic barrier on the outer peripheral side of the fixed magnetic magnet, and the magnetic path cross-sectional area on the inner peripheral side of the fixed magnetic magnet The position of the cavity provided in can be appropriately changed according to the coercive force of the permanent magnet used, the strength of the magnetic field generated by the magnetizing current, and the like.

(4) During operation, the permanent magnet is magnetized by a magnetic field generated by a pulsed d-axis current for a very short time, and the amount of magnetic flux of the permanent magnet is irreversibly changed, and the phase is advanced with respect to the induced voltage of all the magnets. By continuously energizing the current, the amount of interlinkage magnetic flux of the armature winding generated by the current and the permanent magnet is changed.

  That is, if the amount of magnetic flux of the permanent magnet is reduced by the pulse current and the current phase is further advanced, magnetic flux generated by the current in the opposite direction to the magnetic flux is generated. Terminal voltage can be reduced. Note that advancing the current phase is equivalent to flowing a negative d-axis current component.

  In such current phase advance control, when the current phase is advanced, a d-axis current flows, the magnet is demagnetized, and the amount of magnetic flux is somewhat reduced. However, since the magnetic field is greatly demagnetized by the pulse current, there is an advantage that the reduction of the magnetic flux amount is small in proportion.

Sectional drawing of the rotor and stator in the 1st Embodiment of this invention. Sectional drawing which shows the state with the largest flux linkage of a magnet. Sectional drawing which shows the state which generated the magnetic field which reduces the magnetic force of a variable magnetic magnet with the electric current of a coil. Sectional drawing which shows the state which the magnetic force of the variable magnetic force magnet decreased with the reverse magnetic field by an electric current. FIG. 3 is a cross-sectional view showing a state in which a variable magnetic force magnet is magnetized in the reverse direction by a reverse magnetic field caused by an electric current and the linkage flux of the magnet is minimum. Sectional drawing which shows the state which generate | occur | produced the magnetic field which reduces the magnetic force of the variable magnetic magnet which reversed the polarity with the electric current of the coil. Sectional drawing which shows the state which reduced the magnetic force of the variable magnetic magnet which reversed the polarity with the magnetic field by an electric current. Sectional drawing in which a variable magnetic force magnet is magnetized in the reverse direction by a reverse magnetic field due to electric current, and the linkage flux of the magnet is maximum. The figure which shows the operating point change of a low coercive force magnet, and the magnetic characteristic of a typical magnet. Sectional drawing which shows the state at the time of demagnetization in 1st Embodiment. Sectional drawing which shows the relationship between the magnetic barrier in this invention, and q-axis magnetic flux. Sectional drawing which shows the effect | action of the short circuit coil in this invention. The schematic diagram which shows the structure of the 2nd Embodiment of this invention. The schematic diagram which shows the structure of the 3rd Embodiment of this invention. Sectional drawing of the rotor of patent document 1. FIG. The schematic diagram which shows the effect | action of the rotor of patent document 1. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Rotor 2 ... Rotor core 3 ... Variable magnetic magnet 4 ... Fixed magnetic magnet 5 ... Cavity (magnetic barrier)
6. Cavity at the end of permanent magnet (magnetic barrier)
7 ... Magnetic pole part 8 ... Short-circuit coil

Claims (17)

The magnetic pole of the rotor is formed by using two or more kinds of permanent magnets whose coercive force and magnetization direction thickness are different from those of other permanent magnets.
The two or more types of permanent magnets are arranged in series on the magnetic circuit, and the coercive force and the magnetization direction thickness of the two or more types of permanent magnets are compared with the two or more types of permanent magnets arranged in series. Permanent magnets with large product are arranged in parallel on the magnetic circuit,
A permanent magnet that forms a magnetic pole by magnetizing a permanent magnet having a small product of coercive force and magnetization direction thickness among the two or more types of permanent magnets arranged in series by a magnetic field generated by an armature winding current A permanent magnet type rotating electrical machine characterized by irreversibly changing the amount of magnetic flux. Each magnetic pole of the rotor is formed using two or more kinds of permanent magnets having a product of coercive force and magnetization direction thickness different from those of other permanent magnets.
In each of the magnetic poles, the two or more kinds of permanent magnets are arranged in series on the magnetic circuit at the center of the magnetic pole, and the two or more kinds of permanent magnets arranged in series are arranged between the magnetic poles of the magnetic poles. On the other hand, among the two or more types of permanent magnets, permanent magnets having a large product of coercive force and magnetization direction thickness are arranged in parallel on the magnetic circuit,
In each magnetic pole, the magnetic field created by the current of the armature winding is used to magnetize the permanent magnet having a small product of the coercive force and the magnetization direction thickness among the two or more types of permanent magnets arranged in series. A permanent magnet type rotating electrical machine characterized by irreversibly changing the amount of magnetic flux of a permanent magnet to be constituted. The first magnetic pole formed by using two or more types of permanent magnets having a product of coercive force and magnetization direction thickness different from those of other permanent magnets, and the first magnetic pole arranged on both sides of the first magnetic pole are A magnetic pole of a rotor is formed from a second magnetic pole configured using a permanent magnet having a large product of a coercive force and a magnetization direction thickness among the two or more types of permanent magnets having different polarities,
In the first magnetic pole, a magnet having a small product of the coercive force and the magnetization direction thickness among the two or more types of permanent magnets is arranged at the center of the magnetic pole. Among the two or more types of permanent magnets, permanent magnets having a large product of coercive force and magnetization direction thickness are arranged in parallel on the magnetic circuit,
A magnet having a small product of coercive force and magnetization direction thickness disposed in the center of the first magnetic pole, and a magnet having a large product of coercive force and magnetization direction thickness disposed in the second magnetic pole are magnetized. Placed in series on the circuit,
The first magnetic pole arranged in series on the magnetic circuit has a small product of the coercive force and the magnetization direction thickness, and the second magnetic pole has a large product of the coercive force and the magnetization direction thickness. A magnet having a large product of the coercive force and the magnetization direction thickness disposed between the magnetic poles of one magnetic pole is disposed in parallel on the magnetic circuit;
In the first magnetic pole, a permanent magnet having a small product of coercive force and magnetization direction thickness is magnetized from the two or more types of permanent magnets arranged in series by the magnetic field generated by the current of the armature winding. A permanent magnet type rotating electrical machine characterized by irreversibly changing the amount of magnetic flux of a permanent magnet constituting a magnetic pole. Each magnetic pole of the rotor is formed using two or more kinds of permanent magnets having a product of coercive force and magnetization direction thickness different from those of other permanent magnets.
In each of the magnetic poles, a permanent magnet having a large product of coercive force and magnetization direction thickness among the two or more types of permanent magnets is disposed at the center of the magnetic pole, and the center of the magnetic pole is disposed between the magnetic poles. The two or more types of permanent magnets are arranged in series on the magnetic circuit, with a magnet having a large product of the coercive force and the magnetization direction thickness interposed therebetween,
For two or more kinds of permanent magnets arranged in series, a permanent magnet having a large product of the coercive force between the magnetic poles and the magnetization direction thickness is arranged in parallel on the magnetic circuit,
In each magnetic pole, the magnetic field created by the current of the armature winding is used to magnetize the permanent magnet having a small product of the coercive force and the magnetization direction thickness among the two or more types of permanent magnets arranged in series. A permanent magnet type rotating electrical machine characterized by irreversibly changing the amount of magnetic flux of a permanent magnet to be constituted. In the magnet type rotating electrical machine according to claim 1, claim 2 or claim 4,
There are two types of permanent magnets arranged in series on the magnetic circuit: a magnet having a small product of coercive force and magnetization direction thickness and a magnet having a large product of coercive force and magnetization direction thickness. A permanent magnet type rotating electrical machine, wherein magnets are arranged in a magnetic core of a rotor. In the permanent magnet type rotating electrical machine according to any one of claims 1 to 5,
A permanent magnet type rotating electrical machine characterized in that magnets arranged in parallel on a magnetic circuit are arranged substantially on a straight line or on a V-shape. In the permanent magnet type rotating electrical machine according to any one of claims 1 to 6,
A permanent magnet type rotating electrical machine comprising: a magnet disposed in parallel on a magnetic circuit, the magnet being disposed substantially on the q-axis of the side surface of the magnetic pole, and a magnet disposed in the center of the magnetic pole. The permanent magnet type rotating electrical machine according to any one of claims 1 to 7,
A permanent magnet type rotating electrical machine characterized in that a portion having a large magnetic resistance is provided in a magnetic path of a magnet having a large product of coercive force and magnetization direction thickness. The permanent magnet type rotating electrical machine according to any one of claims 1 to 8,
A permanent magnet type rotating electric machine, characterized in that a short-circuit coil is provided on a rotor. The permanent magnet type rotating electrical machine according to any one of claims 1 to 9,
A permanent magnet type rotating electrical machine characterized in that the magnetoresistance in the q-axis direction is larger than the magnetoresistance in the d-axis direction excluding the magnet portion. The permanent magnet type rotating electrical machine according to any one of claims 1 to 10,
The air gap length in the q-axis direction is larger than the air gap length in the d-axis direction. The permanent magnet type rotating electrical machine according to any one of claims 1 to 11,
The magnetic field created by the current of the armature winding magnetizes a permanent magnet having a small product of the coercive force and the magnetization direction thickness among two or more types of permanent magnets to irreversibly reduce the interlinkage magnetic flux by the permanent magnets.
After this decrease, a magnetic field generated by the current is generated in the opposite direction to magnetize the permanent magnet having a small product of the coercive force and the magnetization direction thickness among two or more types of permanent magnets, and the amount of flux linkage is irreversible. A permanent magnet type rotating electrical machine characterized in that it is increased. The permanent magnet type rotating electrical machine according to any one of claims 1 to 12,
The permanent magnet is magnetized by a magnetic field generated by a d-axis current to change the amount of magnetic flux of the permanent magnet irreversibly, and a torque is controlled by a q-axis current at the same time as a d-axis current for magnetizing the permanent magnet flows. Magnet rotating electric machine. The permanent magnet type rotating electrical machine according to any one of claims 1 to 13,
During operation, the permanent magnet is magnetized by a magnetic field generated by a d-axis current to irreversibly change the amount of magnetic flux of the permanent magnet. A permanent magnet type rotating electrical machine characterized by being reversibly changed. The permanent magnet type rotating electrical machine according to any one of claims 1 to 14,
Magnetize a permanent magnet whose product of coercive force and magnetization direction thickness is smaller than the others so that the total interlinkage magnetic flux of the permanent magnet is large at the maximum torque, and at light loads with small torque and at medium and high speed rotation ranges. Then, the permanent magnet type rotating electrical machine is characterized in that the permanent magnet having a product of the coercive force and the magnetization direction thickness smaller than the others is magnetized by a magnetic field caused by an electric current to reduce the total interlinkage magnetic flux of the permanent magnet. The permanent magnet type rotating electrical machine according to any one of claims 1 to 15,
When the rotor reaches the maximum rotation speed with the magnetic flux linkage minimized by irreversibly changing the magnetic pole magnet, the induced electromotive force of the permanent magnet is less than the withstand voltage of the inverter electronic component that is the power supply of the rotating electrical machine A permanent magnet type rotating electrical machine. The permanent magnet type rotating electrical machine according to any one of claims 1 to 16,
When assembling the rotor into the stator, the permanent magnet with a small product of the coercive force and the magnetization direction thickness is demagnetized or the interlinkage magnetic flux of the permanent magnet is reduced by reversing the polarity. A permanent magnet type rotating electrical machine.

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